All types of conductors are subject to transient voltages which potentially disable unprotected electronic and electrical equipment. Transient incoming voltages can result from lightning, electromagnetic pulses, electrostatic discharges, ground loop induced transient or inductive power surges.
More particularly, transients must be eliminated from electrical connectors commonly used in radar, avionics, sonar and broadcast. The need for adequate protection is especially acute for defense, law enforcement, fire protection, and other emergency equipment. used. These machined surfaces result in matte finishes. Alternatively, disk substrates could be precision blanked from flat precision cold-rolled aluminum-alloy sheet or other metal strip whose surface finish would replicate that of the work rolls used in the finishing pass of the rolling mill. For example, with work rolls that have been ground and polished to a mirror-bright finish, a metal strip with a mirror-bright surface finish would result. Typically, the aluminum-alloy disk is coated with an electroless-deposited nickel-phosphorus alloy, which is nonmagnetic. However, in order for this plating to adhere properly to the matte surface of an aluminum-alloy disk, a zincate solution is used to dissolve the surface aluminum oxides, hydroxyoxides, and hydrous oxides, and to provide a zinc metal monolayer by replacement reaction. The surface of the electroless-deposited-nickel-phosphorus-alloy-coated aluminum-alloy disk must be lapped and polished prior to the subsequent plating or sputter-deposition of the magnetic layer. Therefore, the fabrication must engage in the laborious lapping and polishing of the disk substrate. This lapping and polishing step is expensive and adds substantial costs to the final disk product. Furthermore, it is extremely difficult to obtain flaw-free electroless-deposited nickel-phosphorus-alloy coatings. Nodules, pits, and bumps occur in these coatings and such defects cause recording errors.
In addition, the electroless-deposited nickel-phosphorus alloy is very prone upon heating to recrystallization, where the nonmagnetic (actually, paramagnetic) nonequilibrium extremely microcrystalline supersaturated-solid-solution single phase of nickel and phosphorus separates into two equilibrium crystalline phases, namely, nickel, which is ferromagnetic, and nickel phosphide. The resulting ferromagnetism renders the media useless for the magnetic-recording application.
It is yet another object of the present invention to provide a process for coating a surface with an overvoltage protection viscous coating material.
Another object of the invention is to provide an electrically non-linear thin membrane or tape.
It is a related object of the present invention to provide a material wherein the clamp voltage changes when pressure is applied to the material.
The foregoing and other objects of the invention are achieved by a method of combining an transient overvoltage protection material, for example, a binder substance with conductive particles, each in amounts sufficient so that the combination of the binder substance and the conductive particles exhibit transient overvoltage protection material properties and a solvent. Furthermore, the above objects are also achieved by a process for coating a surface with such viscous coating material.